August 31- September 2- NABOS mooring recovery
I peeked out my port holes at about 3:30 this morning and was rewarded with beautiful views of softening pack ice. This is the first time the temperature has dipped below freezing. I planned to go to the bow (front) so I made sure I dressed warmly which ended up being a good idea because it was cold and windy with snow flurries. I wore wool leggings, waterproof work pants covered with snow pants, long-sleeved wool undershirt, wool hoodie, parka, heavy wool socks, warm waterproof wool-lined boots, heavy duty waterproof mittens, wool hat, and a neck warmer. Once I was on the bow, it was so fascinating watching the ship break through the ice. The ice was thin and cracked easily in multiple places, pushing the pieces of ice aside causing little waves. It felt like the ship was just floating. She was so graceful.
Today was NABOS’s first mooring recovery, and an exciting one at that. At the top of the mooring were seven thermistors (see photo), very sensitive temperature probes. The thermistors were attached with cable ties to very strong rope between the five small floats. To avoid any damage to the thermidors, they were picked up by crew members in a Zodiac, a rubber boat. The temperature data on the thermidors is collected electronically. Once the thermidors are recovered the data is downloaded. Next, a rope was hooked up to the very large yellow float, ~1m (37 in) in diameter, and pulled in by the mooring winch. After the floats a few instruments came up that have not been seen on this cruise, including one that looks like a mini yellow submarine. Stay tuned and there will be more information tomorrow.
We are now headed northeast for a mooring recovery. We are still between Severnaya Zemlya Island and the New Siberian Islands, but a little more north.
Breakfast: oatmeal, ham and cheese
Lunch: chicken noodle soup, baked fish with tomato/garlic/carrot sauce, rice, and salad
Tea Time: grilled ham, cheese, tomato and olive sandwiches, and honeydew
Dinner: pork stuffed with vegetables, boiled potatoes, and salad
Today is foggy and overcast, and as the day progressed it got windier and rainier with huger masses of slushy pack ice. Every time the engine would start chugging, breaking ice, I would run out to the helo deck. The chugging reminds me of Tommy the Little Engine chugging up the hill saying “I think I can, I think I can”.
I would like to continue the conversation from yesterday and talk about a couple of instruments that were recovered.
After the thermistors and small floats were removed the mooring crew detached more floats, but bigger ones this time. These floats are ~ 1m (37 in) and ¾ m( 30 in) in diameter, made out of steel and filled with air, unlike the glass floats covered with plastic ‘hard hats’.
Next, the beacon, small yellow cylindrical instrument, was removed. The beacon helps the crew find the mooring. If you remember from the 24 August post I talked about being on the bridge deck while the science crew was trying to find the mooring. The beacon (transducer) is the instrument the hydrophone communicates with. Scientists locate the mooring by putting a hydrophone in the water. The hydrophone is both a speaker and microphone that talks to the beacon on the mooring. The beacon detects to the signal from the hydrophone and replies. It makes a sound, similar to a beep, when found.
Then, the Acoustic Doppler Current Profiler (ADCP) came up. The ADCP is basically an echo sounder that measures sound frequency by measuring water velocity using the Doppler effect.
The instrument sends out a sound signal (ping) at a known frequency. Tiny particles that are suspended everywhere in the water act as reflectors and send back an echo that is recorded by the instrument. But since these particles are moving with the water currents, the frequency of the echo is slightly different from the original ping (that is because of the Doppler effect, the same effect that makes the siren of a police car change it’s pitch as it’s passing -google-). From these minute differences in frequency the instrument can figure out speed and direction of water currents.
Last, my favorite, the McLane Moored Profiler (MMP), also known as a ‘monkey’ and affectionately as the ‘little yellow submarine’. The black cylindrical part with holes on top of the MMP is the CTD head which measures conductivity (salinity), temperature, and pressure (depth). The antennae probes on top measure the water current. The MMP has a water pump and glass ball weight in the inside.
The MMP is protected on both ends with bumpers, flying saucer-looking instruments, that move up and down the line. The black part between the two white plastic plates is a wheel barrow wheel. There is a lot of multiple use of materials on the ship.
Breakfast: corn porridge, ham and cheese
Lunch: beef barley soup, meatballs, buckwheat, and salad
Tea Time: beet/pea/potato/carrot salad, and apples
Dinner: beef barley soup, pork roast, pasta, and salad
It was a beautiful morning, partly cloudy and sunny. By early afternoon it became overcast and started to rain. It’s another special day. NABOS deployed the first mooring of the cruise. Instead of recovering instruments, the instruments were put in the water. I got to see the McLane Moored Profiler (MMP), the ‘little yellow submarine’, go back into the water. When the MMP hit the water it just started randomly sputtering around in circles before going under the water. The NABOS team has been very busy with CTD casts. I have talked a little bit about the rosette and CTDs already. So, what happens when the CTD is recovered? When the rosette first arrives, the sensors are immediately rinsed with fresh water. Otherwise, salt crystals would form from the salt water in the ocean. Then team members start collecting water samples. Some scientists and students will use the water samples and start their research onboard the ship, while other samples are going to science institutes and universities for further study. Depending on what is being studied, it could take quite a while to examine the data.
PhD student Stefan Büttner, with the help of PhD student Miriam Hansen, is collecting water samples to study suspended particle matter. Stefan is interested in the organic and inorganic particles in the water column, and how they are transported from the sea shelf to the basin. Stefan does not do all of his research onboard. He filters 1 ltr bottles of water to collect a concentration of particles to take back home to study. So far, he has about 200 filters and plans on doing 200 more. The filters are weighed before collecting particles and then again at home. This is so he will know how much particles he has collected.
Chemical Oceanographer Matt Alkire is studying dissolved oxygen, oxygen in the water. Since gases are the most susceptible to contaminants he took his water samples first. As soon as the water samples were taken, he put in manganese chloride (MnCl2) and sodium hydroxide/sodium iodine (NaOH/NaI) to keep the dissolved oxygen set. These chemicals are called ‘pickling reagents’.
PhD student Naeun Jo is collecting water samples to study the primary production of phytoplankton with the help of fellow PhD student Kim Kwanwoo. I will go into more detail about their research later.
PhD student Channing Bolt is interested in chemical oceanography. She is the graveyard shift team leader of water sampling.
While team members are collecting water samples, Susanne Spahic, downloads data from the underwater vision profiler (UVP). The UVP measures particles and zooplankton in the water column. Susanne connects the UVP with a data and power cable to download the information for processing. She works with PhD student Andreas Rogge who is studying particle dynamics.
We continue to head a little south to recover moorings and deploy CTD casts. The more south we go, the less ice there will be.
Breakfast: eggs and bacon
Lunch: salami olive soup, beef/cabbage casserole, and pickles
Tea Time: pastry, and honeydew
Dinner: turkey, mashed potatoes, and salad